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201.
Baker BJ Tyson GW Webb RI Flanagan J Hugenholtz P Allen EE Banfield JF 《Science (New York, N.Y.)》2006,314(5807):1933-1935
Novel, low-abundance microbial species can be easily overlooked in standard polymerase chain reaction (PCR)-based surveys. We used community genomic data obtained without PCR or cultivation to reconstruct DNA fragments bearing unusual 16S ribosomal RNA (rRNA) and protein-coding genes from organisms belonging to novel archaeal lineages. The organisms are minor components of all biofilms growing in pH 0.5 to 1.5 solutions within the Richmond Mine, California. Probes specific for 16S rRNA showed that the fraction less than 0.45 micrometers in diameter is dominated by these organisms. Transmission electron microscope images revealed that the cells are pleomorphic with unusual folded membrane protrusions and have apparent volumes of <0.006 cubic micrometer. 相似文献
202.
R. Sunley R. Cannon D. Eyre R. H. A. Baker A. Battisti N. Giltrap D. Griessinger 《EPPO Bulletin》2012,42(1):89-92
The decision‐support scheme (DSS) for action at outbreaks developed under PRATIQUE (Enhancements of Pest Risk Analysis Techniques) brings together a set of guidance and tools, using the CAPRA application. The DSS is initiated by the collation of key information on the current outbreak situation, and then compares candidate measures in order to derive a strategy for action and/or contingency. It is hoped that this deliverable will assist national plant protection organizations (NPPOs) to address and justify eradication campaigns effectively. The rationale behind the DSS and its key features are presented and discussed. 相似文献
203.
D. Eyre R. H. A. Baker S. Brunel M. Dupin V. Jarošik D. J. Kriticos D. Makowski J. Pergl P. Reynaud C. Robinet S. Worner 《EPPO Bulletin》2012,42(1):48-55
The assessment of the suitability of the climate for pest establishment is an important part of pest risk analysis (PRA). This paper describes the work undertaken by the EU 7th Framework project PRATIQUE (Enhancements of Pest Risk Analysis Techniques) to develop guidance for this component of PRA. Firstly, there is a guide to rating the suitability of the climate in the PRA area using qualitative methods. Secondly, a Decision‐support scheme (DSS) has been created to assist analysts in deciding whether to map climatic suitability, and to guide the selection of the most appropriate method from the large number available. The process of selecting a climatic mapping method is based on a review of the pest’s climatic responses and distribution. A spreadsheet provides a comparison of the potential problems that can arise, depending on the mapping method and on the amount and quality of available data. Diagrams are provided to help choose the location data category that best represents the possible biases in the known distribution of the pest. A second spreadsheet provides general information on the differences and similarities of each method in terms of categories such as functionality, ease of use and quality assurance. A variety of data, tools and supporting documents are available as appendices to the DSS. All of the tools and guides are freely available online. 相似文献
204.
E. Madejón A. I. Doronila P. Madejón A. J. M. Baker I. E. Woodrow 《Agroforestry Systems》2012,84(3):389-399
The effect of the addition of biosolids combined with a native arbuscular mycorrhizal inoculum on growth of a eucalypt (Eucalyptus cladocalyx), and on trace element stabilization of arsenical sulphidic gold mine tailings was tested. A glasshouse trial was established
using four substrates: tailings (T); tailings with a layer of topsoil (TS); tailings amended with 100 t ha−1 biosolids (LB), and tailings amended with 500 t ha−1 biosolids (HB). Half of the pots were inoculated with a mixture of Glomus sp. (WUM51–9227), Scutelospora aurigloba (WUM51–53) and Acaulospora laevis (WUM46) culture mix, and others were uninoculated controls. Two seeds per pot were sown. Leaf and stem weights, leaf area
and plant height were measured for each plant. Nutrients and trace element concentrations in leaves and stems were determined.
Addition of biosolids significantly increased mycorrhizal colonization (both ectomycorrhizal and arbuscular mycorrhizal)
in roots. Biosolids clearly increased the very early establishment and growth of the eucalypts. In general, mycorrhizal inoculum
increased plant biomass production and nutrient uptake. Trace element concentrations in trees of the biosolid-amended pots
were in general high, however, mycorrhizal inoculation could reduce the uptake of toxic elements by plants. 相似文献
205.
206.
B.J. Mansell MS L.A. Baker PhD J.L. Pipkin PhD G.D. Potter PhD R.C. Bachman MS L.J. Perino PhD DVM G.O. Veneklasen DVM J.C. Haliburton PhD DVM M.A. Buchholz-Bryant MS 《Journal of Equine Veterinary Science》2001,21(9)
An experiment was performed to determine the effects of Ca and P supplementation, inactivity, and subsequent aerobic exercise on bone metabolism in young, mature, and aged horses. Twelve stock-type geldings were blocked into three groups: 2 and 3, 7 to 11, and 15 to 21 years of age. Horses within age groups were evenly divided and randomly assigned to one of two dietary treatments; control (C) or Ca and P supplementation (T). Horses consuming C and T received about 133% and 275% of National Research Council (NRC) requirements for Ca and P, respectively. The trial consisted of eight 21-day periods. During periods I, II, and III, all horses were inactive and received no forced exercise. During periods IV, V, VI, VII, and VIII, all horses were placed on an ascending aerobic exercise regimen. Blood samples were taken at the beginning of period I and at 21-day intervals thereafter to determine serum concentrations of osteocalcin (OST) and type I carboxyterminal telopeptide (ICTP). Dorsal-palmar and lateral-medial radiographs were taken of the left third metacarpal at the beginning of period I and at 21-day intervals thereafter to monitor changes in bone densities, as indicated by radiographic bone aluminum equivalencies (RBAE). Mean serum OST was affected by age (P < .004) and the interaction of time and age (P < .006). Mean serum ICTP was affected by age (P < .001), time (P < .001), the interaction of time and age (P < .001); and the interaction of time and treatment (P < .05). There was an effect of treatment on overall mean medial (MRBAE; P < .04) and total (TRBAE; P < .04) RBAE. Overall mean dorsal RBAE (DRBAE; P < .001), palmar RBAE (PRBAE; P < .003), lateral RBAE (LRBAE; P < .001), MRBAE (P < .001), normalized MRBAE (P < .001), TRBAE (P < .05), and normalized TRBAE (P < .05) were affected by time. There was an effect of the interaction of time and age on overall mean DRBAE (P < .05), LRBAE (P < .002), MRBAE (P < .02), normalized MRBAE (P < .02), TRBAE (P < .005), and normalized TRBAE (P < .005). Overall mean DRBAE (P < .02) and PRBAE (P < .001) were affected by the interaction of time, treatment, and age. Biochemical and radiographic data from this experiment indicate that dietary Ca and P supplementation may affect bone remodeling in aerobically exercised horses of varying ages following a period of inactivity. Furthermore, the data indicate that bone in horses of varying ages responds differently to inactivity and exercise. 相似文献
207.
Sartin JL Shores MA Schwartz DD Kemppainen RJ Baker J 《Domestic animal endocrinology》2000,19(2):85-92
Disease has profound effects on the immune system, endocrine system, and on the growth process. Since diseases are catabolic to the animal, there is current interest in the possible role of anabolic hormones to counter the effects of disease in general and minimize the effects of a disease process on growth and development. A number of anabolic hormones, such as growth hormone (GH) and estradiol + progesterone (EP), have been studied for their role in enhancing growth and stimulating immune function and are thus candidates for hormonal intervention in disease processes. GH has been shown to be effective in countering some of the deleterious effects of endotoxemia but was ineffective in a parasitic disease model. Studies with EP have shown similar success with both endotoxemia and a parasitic disease model. Moreover, GH and EP do not share a common mechanism of action, suggesting that the effects are not simply due to anabolic actions. While the mechanism of action of GH in endotoxemia has been examined, the effects of EP are via an unknown mechanism, possibly by inhibition of IL-I action or inhibition of nitric oxide overproduction. 相似文献
208.
209.
David P. Blackburn Matthew G. Hamilton Chris E. Harwood Thomas G. Baker Brad M. Potts 《Annals of Forest Science》2013,70(5):461-470
Context
Stem straightness is an important trait for growers and processors of Eucalyptus globulus logs for solid-wood products.Aims
The aims of the study were to determine the extent of genetic variation in stem deviation from straightness in E. globulus and assess the utility of a six-point subjective scoring method as a selection criterion for stem straightness.Methods
Two E. globulus progeny trials, grown under solid-wood product regimes, were studied. At age 9 years (post-thinning), stem straightness was measured using both image analysis and a six-point subjective scale. Diameter at breast height (DBH; 1.3 m) was measured at both age 5 (pre-thinning) and age 9 years.Results
Significant additive genetic variation was observed. Strong, positive and significant additive genetic correlations were observed between the stem straightness assessment methods and between DBH at ages 5 and 9 years. Significant positive genetic correlations were shown between subjectively scored stem straightness and DBH at both ages 5 and 9 years.Conclusion
The six-point subjective scoring method is a cost-effective selection criterion for stem straightness in E. globulus. The image measurement technique may be applied where objective estimates of stem straightness are required, for training purposes and to verify subjective scores. 相似文献210.